What documents must be kept for a hazardous area installation?
Abstract
The IEC 60079-14 verification dossier (zone drawings, equipment certificates and instructions, IS descriptive system documents, installation and initial inspection records), the IEC 60079-17 inspection records and, in the EU, the Explosion Protection Document.
Every hazardous area installation needs a verification dossier: the set of documents showing that the equipment and the installation comply. IEC 60079-14 requires it to be prepared for every installation and kept on site, or kept elsewhere with a note on site saying who owns it and where it is. It holds the area classification, the equipment certificates and instructions, the installation records and the initial inspection, and it is then extended by the inspection and repair records of IEC 60079-17 and IEC 60079-19. In the EU the employer must also keep the Explosion Protection Document.
Short answer
- Site information: area classification drawings and schedules (zones, extents, gas or dust group, temperature class or ignition temperature, ambient and external influences).
- Equipment information: certificates, EU or other declarations of conformity, manufacturer's instructions, Specific Conditions of Use for certificates with an "X" suffix, an equipment list with locations.
- Installation information: cable and wiring drawings, cable entry selection records, circuit identification schedules, intrinsic safety descriptive system documents and calculations, purge and other calculations.
- Inspection records: the initial inspection report, then every periodic and sample inspection, defects and corrective actions.
- Repairs and changes: repair reports, modification records and replacement equipment details.
- People: evidence of the competence of designers, installers and inspectors.
The verification dossier under IEC 60079-14
The current edition, IEC 60079-14:2024 (edition 6), groups the documentation into site information, Ex equipment information, installation information and personnel competency. The 2007 edition, whose text is publicly available, lists the content in more detail. Read together, a complete dossier contains:
| Part | Typical documents |
|---|---|
| Area classification | Zone drawings with extents; for dust, the maximum permissible layer thickness; gas or vapour group and temperature class or ignition temperature; dust characteristics such as minimum ignition temperatures of cloud and layer |
| Equipment | Certificates and declarations, instructions for erection and connection, documents for equipment with Specific Conditions of Use, manufacturer's or qualified person's declaration where uncertified equipment is used (other than simple apparatus) |
| Intrinsic safety | Descriptive system document for each intrinsically safe system, with the parameter comparison |
| Installation | Wiring plans, records of cable entry selection for each type of protection, circuit identification drawings and schedules, calculations such as purge rates for analyser houses |
| Maintenance support | List and location of equipment, spares, technical information needed for inspection and for repair |
| Initial inspection | Detailed initial inspection report, completed before the installation is brought into service |
The dossier may be kept on paper or electronically. The standard adds that the way a country legally accepts documentation may vary.
Records for inspection and maintenance under IEC 60079-17
IEC 60079-17 requires up-to-date documentation to be available for inspection and maintenance: the zone classification and required equipment protection level for each location, the gas and dust group and temperature requirements, the equipment characteristics (temperature rating, type of protection, IP rating, corrosion resistance), records sufficient to maintain each item in line with its type of protection, and copies of previous inspection records. The results of all initial, periodic and sample inspections must be recorded and retained. An equipment register with unique tag numbers is the usual way to link each item to its certificate, its location and its inspection history, and to track replacements that carry different markings.
The Explosion Protection Document (EU) and its link to the dossier
Directive 1999/92/EC requires the employer to draw up the Explosion Protection Document before work starts and keep it up to date. It must show that explosion risks have been determined and assessed, that adequate measures will be taken, which places are classified into zones, where the minimum requirements apply, that the workplace and equipment are designed, operated and maintained with due regard for safety, and that arrangements have been made for the safe use of work equipment. It must be revised after significant changes, extensions or conversions.
The zone drawings are the shared foundation: the document defines the zones, and the dossier proves that the installation matches them. Turkey's Regulation on the Protection of Employees from the Hazards of Explosive Atmospheres (Çalışanların Patlayıcı Ortamların Tehlikelerinden Korunması Hakkında Yönetmelik, Resmî Gazete 28633, 30 April 2013) requires the same document, the Patlamadan Korunma Dokümanı, in Article 10.
Example: An auditor picks a flameproof motor on a pump skid in Zone 1, IIB T3. A complete file lets him follow the trail in minutes: the zone drawing shows Zone 1, IIB, T3; the register lists the motor's tag, certificate number and marking Ex db IIB T4 Gb; the certificate's conditions are met; the cable entry record shows the gland type chosen; the initial inspection is signed; and the last periodic inspection, two years ago, found no defects.
Common mistakes
- Certificates without the instructions. Specific Conditions of Use and installation instructions are part of the compliance evidence.
- A dossier frozen at handover. Replacements, repairs and modifications must be added, or the register no longer matches the plant.
- No descriptive system document for intrinsically safe loops. Without it, nobody can show that the loop parameters were checked.
- Zone drawings revised without checking the equipment. Any change in classification requires a check that the installed equipment still suits the new zone.
Related on excodex
- Ex installation basics under IEC 60079-14
- Inspection of Ex installations under IEC 60079-17: initial, periodic, visual, close and detailed
- The Explosion Protection Document (EPD) and area classification drawings under ATEX 1999/92/EC
- What must be recorded in the Ex equipment register of an installation?
- Standards spaces: IEC 60079-14, IEC 60079-17
Standards and further reading
- IEC 60079-14:2024, design, selection, erection and initial inspection of electrical installations (edition 6), contents of clause 5 Documentation: sample pages
- AS/NZS 60079.14:2009 (identical text of IEC 60079-14:2007 with national notes), documentation clause and definition of the verification dossier: archive.org
- IEC 60079-17:2013, documentation clause (verification dossier for inspection and maintenance): sample pages; IS/IEC 60079-17:2007, public text of the earlier edition: archive.org
- Directive 1999/92/EC, Article 8 (Explosion Protection Document): legislation.gov.uk
- Turkish regulation on explosive atmospheres at work, Resmî Gazete 28633 (30 April 2013), Article 10: resmigazete.gov.tr
- IEC 60079-19, equipment repair, overhaul and reclamation (repair records)
This article is general technical information prepared by the excodex editorial team. It does not replace the applicable standards, the equipment certificates and instructions, national regulations or the assessment of a competent person.